From Shady Valley TN travel North on 133 to Damascus, VA. Most people are in this area to ride the snake (421), but a short run north on 133 is worth the time.
The road is relatively level because it follows a stream through the valley. The two lanes are often covered by large overhanging trees which make for a shady trip on hot days. About half way through the 14 miles you will ride through a very short tunnel. It was originally put there so a railroad didn't have to divert around a ridge that comes into the valley. It is advertised as "the shortest tunnel" in the East, US or World. Depending on who is telling the story.
This is one of those slow down and enjoy the scenery routes. Sine it is not a primary road it may have sections that need some repair. With very few homes and no businesses along the way you often have the road all to yourself. Stopping at the tunnel is worth it, there is a information marker at the site.
At the southern end is Shady Valley. The Motorcycle friendly store there has all kinds of t- shirts and patches for US 421, The Snake. The food selection is limited to burgers and fries type meals. On the weekend Shady Valley will be PACKED with motorcycles and sports cars. Damascus, VA on the north is a small town with a few amenities. You can tell that it was once more populated and a hub for the area, but that era has long passed.